【发布时间】:2020-04-29 20:43:39
【问题描述】:
我正在使用 scrapy 从单个域中抓取所有链接。我正在关注域上的所有链接,但将所有链接保存在域外。以下刮板工作正常,但我无法从刮板内访问成员变量,因为我使用CrawlerProcess 运行它。
import scrapy
from scrapy.crawler import CrawlerProcess
class MySpider(scrapy.Spider):
name = 'myspider'
start_urls = ['https://example.com']
on_domain_urls = set()
off_domain_urls = set()
def parse(self, response):
links = response.xpath('//a/@href')
for link in links:
url = link.get()
if 'example.com' in url and url not in self.on_domain_urls:
print('On domain links found: {}'.format(
len(self.on_domain_urls)))
self.on_domain_urls.add(url)
yield scrapy.Request(url, callback=self.parse)
elif url not in self.off_domain_urls:
print('Offf domain links found: {}'.format(
len(self.on_domain_urls)))
self.off_domain_urls.add(url)
process = CrawlerProcess()
process.crawl(GoodOnYouSpider)
process.start()
# Need access to off_domain_links
如何访问 off_domain_links?我可能可以将其移至全局范围,但这似乎是 hack。我也可以附加到文件,但如果可能的话,我想避免文件 I/O。有没有更好的方法来返回这样的聚合数据?
【问题讨论】:
标签: python python-3.x web-scraping scrapy